Variable flame-orifice gas burner



July 15, 1952 P. F. SWEYNSON ETAL VARIABLE FLAME-ORIFICE GAS BURNER 4 Sheets-Sheet 2 Filed July 7, 1948 VIII/.1452:

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July 15, .P. F. SWENSON EI'AL 2,603,233

- I VARIABLE .FLAME-ORIFICE GAS BURNER Filed July 7, 1948 ,4 Sheet s-Sheet 3 I IN V EN TORS Arron/n76 P. F. swENsoN ETAL VARIABLE-FLAME-ORIFICE GAS BURNER Jqly 15, 1952 4 Shets-Sheet 4 Filed July 7, 1948 INVENTORS E Swewswv BY ML 7-0 APPA v04 ,3 I I Mm 3 l Arman/75 Patented July 15, 1952 VARIABLEFLAME-ORIFICE ens BURNER Paul F. Swenson, Cleveland HeightsQand Milton F. Pravda; Bedford, Ohio, assignors to The Cleveland 'Resear'ch Corporation, Ohio, a corporation of Ohio Cleveland,

Application July '1, 1948, Serial No.3).346

13 Claims. (01. 153-417) This invention relates to gas burners of the gas and air mixing type in which a velocity discharge of gas induces a flow of air for mixing therewith and, more particularly, to gas burners of this type in which means is provided for simultaneously controlling the velocity discharge of the gas and the delivery of the gas and air mixture at the combustion opening.

An object of the present invention is to provide animproved gas burner of the type mentioned which will be highly efflcient, safe and reliable in operation and which is of such simple and lightweight construction that it can be economically manufactured and will be well suited for use in certain kinds of gas burning equipment, such as cooking stoves.

Another object of this invention is to provide an improved construction for a gas burner of the kind indicated in which novel means is employed for controlling the velocity gas discharge and the delivery of the gas and air mixture.

Still another object is to provide an improved gas burner construction of the character mentioned in which the velocity discharge of gas and the delivery of the gas and air mixture are varied simultaneously so as to produce an eiiicient, safe and reliable functioning throughout the entire range of burner operation and in which the burner will have a very satisfactory turndown ratio.

A further object is to provide an improved gas burner of this character which will be adaptable for either right or left hand installation such that only a minimum number of different burners and burner parts will need to be manufactured and carried in stock.

Yet another object is to provide a gas burner of the character mentioned which will be substantially foolproof when embodied in a domestic cooking stove and which can be quickly and easily disassembled for cleaning purposes and then readily reassembled, by persons who are not skilled mechanics.

As another of its objects this invention provides an improved gas burner in which a mixing tube and a rotary control shaft are carried by a common base and wherein motion derived from the shaft is utilized to actuate a gas control valve and a shutter member for controlling. the mixture delivery opening.

Still another object is to provide an improved gas burner of this kind in which novel cam and lever means is employed ineifectively utilizing the rotary movement of said shaft for causing the desired actuation of the control valve and shutter member. I

As a further object this invention provides an improved gas burner of the character mentioned in which a pilot burner of a novel construction and arrangementis employed.

The invention can be further briefly summarized as consisting in certain novel combinations and arrangement of parts hereinafter described and particularly set out in the claims hereof.

In the accompanying'sheets of drawings:.

Fig. 1 is apartial plan view showing a stove equipped with the improved burner and inwhich a pair of the burners are installed in right and left hand positions;

Fig. 2 is a plan view of the burner on a larger scale and detached from the stove;

Fig. 3 is a vertical section taken through the burner on line 3-3 of Fig. 2; I

Fig. 4 is another vertical section taken onlin'e 4-4 ofFig.2;

Fig. 5 is a fragmentary vertical section corresponding-with a portion of Fig. 3 but'showing the gas control valve on an enlarged scale;

Fig. 6 is a partial transverse sectional view taken on line 8-6 of Fig. 3; r

Fig. 7 is a side elevation of the bracket member in which the rotary control shaft is mounted, the bracket being shown detached from the burner assembly;

Fig. 8 is a plan view showing a modified form of the improved gas burner;

Fig. 9 is a vertical section taken through the modified burner on line 9-9 of Fig. 8;

, Fig. 10 is another vertical section taken through the modified burner on line l0lll of Fig. 9;

f Figs. 11, 12 and 13 are transverse sections taken,

but showing another modified form of the burner;

Fig. 15 is a partial plan view of the modified burner of Fig. 14; and

Fig. 16 is a transverse section taken on line |6-l6 of Fig. 14.

' In Fig. 1 a pair of burners Illa and 10b embodying the improved construction are shown installed in a cooking stove H. The stove II is provided with a substantially fiat top l2 having burner openings I2a and I212. The stove is also provided with a gas supply pipe ormanifold l3 which extends across the openings I21; and 12b at a point therebelow and on which the burners Illa and 10b are mounted in right and left hand through the orifice.

'and the burner cap 33.

porting structure also includes a bracketme'mber" [8 in which the rotary control'shaft' l 4* is mounted. As explained hereinafter, the rotary shaft l4 acts indirectly to cause the actuation'ofa valve- 19 which controls the delivery of a velocity'stream of gas to the burner tube 11, and to also'causa '15..

the actuation of a shutter member 20 for varying the size of the combustion: opening 2Jffrom; which the gas and air mixture is delivered atthe. top of the tube l1 fonburning as a sustained The base [5 may-comprise ametal body or-block having an opening 23 in which is mounted a-cylindricalplug' 24which forms-the bodyof the'gas control'valve Ill. The plug 24 extends above the base l6, as shown in Fig. 3; and is frictionally embraced by the lower end of'the burner tube 11 for mounting the latter on the'base. The plug 24 is provided at itslower end with a threaded extension 25Jwhich" is adapted tobescrewedunto an opening of the manifold it for mounting the burner thereon. The plug has a main passage 24 extending axially therethrough and to which gas .under'pressure is supplied bythe manifold. The upper end of thispassage' isin theform of an orifice 28 which is'located substantially on the ,vertical axis of the burner tube-IT so as to discharge a'velocity'stream' of'gas'upwardly in this tube.. The upper.- end of the plug 24 has an upwardly converging tapered valve seat 21 therein surrounding the orifice'26.

The gas control valve [9 also includesa valve member 28 whichis movable in thepassage 24a andicarries a. tapered valve-portion 28a which projects upwardlythrough the orifice 26' and is adapted to. cooperatewith the tapered valve seat 21 for controllingthe velocity discharge of gas Theivalve member is normallyurged'upwardly; that is'in' a direction to ,causeclosing of the orifiCeZBbythe-valve portion 28a, as by means of'a coil spring 29: This spring is confined in the passage 24a andhas-its upper end' in engagement with the valve member 28 and its lower end anchored :on the plug 24 by engagement of.one. of..the"convoluti'ons in the undercut groove 30. The burner tube I! comprises a metal tube charged upwardlyinthe tube by'th'e latter it induces a flow of air into the tube through the opening 82 andsuch air becomes thoroughly 'mixed with the gas.

The gasand air -mixture thus produced in the burner tube I1 is discharged through the combustion opening" 2! for burning asa'sustained'fiame as mentionedabove.

The combustion opening 2| is an'annular space opening laterally around the'top of the burner IDfaIrd; in'this instance, is defined by and located between'the upper end of the shutter member 20 The cap 33 is a platelike metal disk which is supported in spaced relation abov the upperend of the burner tube I1,

" thereto by meansof the screw 3'5.

as by means of a bracket 34 having its lower end welded or otherwise connected to the burner tube. The shutter member 29 comprises a metal sleeve which is in telescoping relation around the burner tube l7 and is slidable thereon so that the upper end of the sleeve is movable toward or away from the cap 33 forvarying the size of the combustion opening 2!.

For thus actuating the shutter member 20 to vary the size of the combustion opening 2 I, a lever 35 is: employed which is pivotally mounted on the bracket i8 and transmits motion to the shutter member from the rotary control shaft l4. The-bracket i8 is here shown as being a sheet metalrnember having a flat bottom wall portion 35' which seats on the base [5 and is attached The bracket [8 also. has laterally spaced upstanding integral side walls Mia and [81) through which the control shaft I4 extends and in which this shaft is journaled for both rotaryand' axial movement.- At a point above the control shaft [4; the side walls 18a and i822 of the bracket 18 are provided with keyhole shaped openings 38' in which a pivot shaft BEl'is mounted;

The lever 35 is here shown as being a bell crank lever having angularly disposed arm portions 35a and 35?). This lever can be in the form of a sheet metal stamping andwhen. so constructed has flange or side wallv portions 40 which are formed integral with'and connect the angularly disposed arms 35a and 35b; The flange portions 46 of the. lever. 35 are provided with openings H. which: register. with the circular portions 38a of the keyhole openings 38 and accommodate the pivot shaft 39 for pivotally'mounting the lever on the bracket. H3.

The outer end of the arm 35a of the lever 35 has laterally spaced fingers located on opposite sides of a slot/43 and" defining a forked portion which straddlesithe:shutter member 20 :and is operably connectedtherewith. For this purpose the shuttenmember 2.01s provided'with opposed slots 28av in which the. adjacentedges of the fingers 42.1of theleverlarm 35a engage. The arm 35b of the bell. cranklever 35 extends downwardly to a point: adjacentthe rotary control shaft [4 and carriesa' follower member. 45 which cooperates with one or the. otherof a pair of right and left hand cams 46a and 48?) mounted on the controlshaft.

Theifollowerx45preferably is not mounted directly -on.the lever arm135b but on a resiliently fiexible auxiliary arm 46 which may consist of a sheet metal part having its upper end rigidly connected with the body of the lever, as by means of welding or'brazing indicated at 41. The follower 45 is formed on the lower end of the auxiliary arm 46 so asto extend laterally toward the control shaft I4 and is adjustable toward or away from the axis of the control shaft by springing of the auxiliary arm relativeto the main arm 35b. The auxiliary arm 46 normally tends to spring away from the main arm 35b, but is confined by an adjusting screw 48 which extends through an opening of the auxiliary arm and is threaded into the main arm 35b. The extreme end or edge 49 of the follower 45'forms a contact surface for engagement with one of the cams 45a and 46b.

The cams 45a and 46b are carried by opposite ends of a sleeve 50 which is mounted on the control shaft l4 between the side walls lBa and 18b of the bracket I8 and is connected with the control shaft as by means of the pin 5|.

be brazed or otherwise connected thereto.

The cam 45a can be referred to asthe right hand cam-becauseit is effective for actuating'the shutter member 20 when the burner lll'is used. in a right hand installation, as represented by the burner Illa of Fig. 1. Similarly, the cam 45b can be referred to as the left hand cam because it iseifective for causing actuation of the shutter member 2c when the burner is installed in a left hand position, as represented by the burner lfib of Fig. 1.

' SinceFigs. 2,3 and 4 show the burner adapted for right hand installation, they show the cam 43a as being in an operating position for cooperation with the follower 45. When the burner is installed in the left hand position the control shaft I4 is shifted axially toward the 7 right, as seen in Fig. 4, to a position in which the left hand cam 4th will cooperate with the follower 45. When the right hand cam 48a is in position for cooperation with the follower 45 the left hand cam 46!) lies adjacent the side wall I811 of the bracket [8 and, conversely, when the left hand cam 45b is in position for cooperation with the follower the right hand cam 46a is located adjacent the side wall I81) of the bracket.

The movement imparted to the shutter member for varying the combustion opening 2| is also utilized to actuate the valve member 28 of the as control valve l9. For this purpose the shutter member 20 is provided with a pin 52 which is mounted thereon so as to extend inwardly through an opening 52a in the wall thereof and is accommodated by an axial clearance slot 53 in the wall of the burner tube ll. The valve member 28 is provided with an actuating stem 54 which is suitably connected therewith and, in this instance, extends upwardly within the burner tubell substantially on the axis thereof. The stem 54 can be formed integral with the valve member 28 or, as here shown may extend into an opening of the valve member and can The valve stem 54 is of a length such that its upper end will be engaged by the pin 52 of the shutter member 29 for causing actuation of the valve member 28 simultaneously with the actuation of the shutter member.

When the shutter member 20 is moved downwardly to cause opening of the valve member 23 for supplying gasto the burner, it also causes r opening of the combustion opening 2| for the delivery of the gas and air mixture for burning as a sustained flame. The size of the combustion opening 2| also controls the supply of air to be mixed with the gas because it controls the amount of air which will be drawn in through the air inlet opening 32 and, when the shutter member is moved downwardly to increase the volume of the velocity gas stream being supplied through the orifice 25, the combustion opening 2i will be simultaneously enlarged to accommodate the increased volume of the gas and air mixture and to also permit a greater amount of air to be drawn in through the air inlet opening 46a will act on thefollower and cause the l lever 35 to be rocked on the pivot shaft 39 in a direction to move the shutter member 20 downwardly to thereby simultaneously open the valve member 28 and enlarge the combustion opening 2|. .The: extent of angular movement imparted to the shaft M will depend upon the size of the burner flame desired. When the burner is to be turned off, the shaft I4 is rotated in the opposite direction, that is in a clockwise direction,"

whereupon the cam 46a, will permit the lever 35 to berocked in the opposit direction by the action of the spring 29 andthis will result in closing of the valve member 28 and closing of the combustion opening 2|.

The end of the follower 45 has a pair of small lugs 56a and 56b thereon which are located at opposite ends of the contact edge 49 which cooperates with the came face 55. The cams 46a and 45b are also provided, respectively, with lugs 57a and 511) which extend substantially radially with respect to theshaft l4 and are located at the high points of the cams, that is to say, at the ends of the cam face spirals. One purpose served by the lugs 51a and 51b is to act as stop members which prevent the follower 45 from riding over the high point of the cams. when the cam 45a has been rotated through the angular movement of the shaft M which pro duces a full opening of the gas control valve IS, the lug 57a of this cam'will come into engagement with the lug 56a of the follower 45 andv will prevent the latter from riding over the high point of the cam and which would, if it occurred; result in a sudden closing of the gas control valve and combustion opening. It will be understood; of course, that when the cam 46b is in cooperation with the follower 45, the lug 57b of this cam cooperates in a similar manner with the lug 56b of the follower.

As shown in the drawings, the control shaft 14 is a double-end shaft, that is to say, it has an end Ma which extends beyond the side wall liia of the bracket 18 and it has an end Mb which ex-- with the end I4 1 of the controlshaft #4 as shown in the drawings, but when the burner is to be used in a left-hand installation the knob I5 is detached from the shaft end Ma and is connected to the shaft end I41). The actuating knob I5 is carried by an extension shaft 53, whose in ner end is provided with lug and slot elements and 6! adapted to cooperate in a complemental relation with similar slot and lug elements 63a and 6| a provided on the ends um and 14b of the'shaft l4.

In Fig. 4 the actuating knob i5 is shown connected to the end" 14a of the control shaft [4 and the complemental lug and slot elements '60, 6m and 60a, 61 are maintained in interfltting engagement by means of a surrounding sleeve 52.

The sleeve is maintained in this position by" means .of a compression spring 63 disposed Thus,

4,:by'. compressing. the. spring 63. When the sleeve 62 has been moved farenough to uncover tha -connection formed by the .complemental lug. and slot elements thisconnectioncan be:disen-- gaged: 7

his desirable that when the shaft I4 is intheposition of rotation .correspondingwith the closed condition of thegas control valve l5, thisshaft and theknoh l5-wil1be locked againstaccidental or unauthorized rotation ina'direction to cause theburner to be turned on. This will prevent theburner from beingturnedon accidentally or by smallchildrenr In the-accomplishment-of this purpose, .the above-described lugs S'Iaand 51b of the cams 46a .and- 46b perform a second function in which theyserve as locking elements. For cooperation with the lugs 51a and 51b the side walls [8a and [8b of the bracket l8 are provided, respectively, with other lockingelements in the'form-of slots 65a and 66b. The slot 66a is so located that when the gas control valve I9 is in its closed condition, the lug 51b of the cam 462) will register with this slot and will be urged in a direction to engage therein by the action of the-spring 63. In accomplishing this function the spring. 63 presses the inner 'end of the sleeve 62 against the side wall 18a of the bracket l8 and, at the same time, reacts through the extension shaft 59 and the control shaft 14 to pull the lug 57b into the slot 56a. While the lug 51?) remains engaged in this slot, the control shaft 14 andth'e knob I5 will be locked against rotation in either direction.

When the burner is to be turned on, inward pressure is first applied to the knob l5, thereby imparting inward axial movement to the shaft to disengage the lug'5lb from the slot 88a. While the lug 51b isheld retracted from the slot why such inward pressure, the knob I5 is rotated in a counterclockwise direction to turn on the burner. As soon as the lug 51b is-shifted out of register with the slot 5611 by the rotation of the shaft I4, the inward pressure on the knob l5 can bereleased and thereafter the lug 57b will be ineffective and will simply ride on the inner face of the side wall We of the bracket l8 while the height of the burner flame is being adjusted. When theburn'er is turned off by clockwise rotation ofthe shaft M, the lug" 511) will return to a position of register with the slot 66a and will be pulled thereinto by the spring 63' to again lock the shaft against rotation.

From the construction and mounting of the cams 46a and 46b, as'above described; it will be understood that when the burner is used in a lefthandjinstallation, the cam 46b will'be in cooperation with the follower 45 and the cam 4611 will be ina position adjacent the: side wall IBb of the bracket I8. During such use of the burner in a left-hand installation, the knob l5'will be connected with the shaft end Nb and the spring 63'will then exert a pull on the shaft M in a direction to cause the lug 51a to cooperate with tion, it is desirable that the burner be capable 8 of being quickly and easily disassembled .so-that the .variousparts thereof can be cleaned by'persons who are-:not skilled mechanics. .To permit this to beaccomplished thepivot shaft 391s quickly detachable from the bracket l8 so as to permit the complete removal of the lever v from the bracket.- The-pivotshaft39 is.accordingly. constructed so as to have sections 39a andlib therein which are of reduced size and are ofa smaller dimension than the width of the slot portion 38b of-the keyhole openings 38 provided in the side walls. l8a-andl8b of the bracket 3. These reduced portions39a and 39b of the pivot shaft arespacedapart thesame distance esthe spacingof the sid walls of the bracket. The pivot'shaft 39 is .mounted'in and extends through the-openings of the flangeportions 40 of the lever 35- -but is axially shiftable therein for bringin'gthe reduced shaft portions39a and 3912 into the keyhole openings 38. When these. reducedportions have been shifted into the keyhole openings they can be moved laterally through the slot portions 38b thereof to thereby disconnect the pivot shaft and lever from the bracket l8.

The portions of the pivot shaft 39 which are located adjacent the reduced portions 39a and 39b are of substantially the same diameter as the circular portions 38a of the keyhole openings 38, that is to say, they are of a larger diameter than the width of the slot portions 38b of the keyhole openings. When the pivot shaft 39 is in its normal fully assembled position, as shown in Fig. 4, the reduced portions 38a and 3% thereof have been shifted axially out of the keyhole openings 38 and the full size portions of the pivot shaft which then engage in the circular portions 38a of the keyhole'openings prevent the pivot shaft from being disengaged from the bracket [8 and maintain the lever 35 pivotally mounted thereon.

The pivot shaft 39 is maintained in the normal position just described above by the action of a stop ring or shoulder 68 provided on the pivot shaft adjacent one end thereof and a compression spring 69 disposed around the pivot shaft adjacent its other end. The spring 69 has one end thereof in engagement with a spring seat 10 which is in the form of a button mounted on this end of the pivot shaft 39 and has its other endin engagement with a cup shaped springseat H which loosely surrounds the pivot shaft. The axial movement for shifting the reduced sections 3% and 39b to the releasing position can be imparted to the pivotshaft by pressure applied to the button!!! by the operators thumb. It will be understood,-of course, that whenthe lever-35 is to bereapplied-to the bracket i 8, the pivot shaft 39 is again shifted axially by thumb pressure applied to the bottom in to bring the reduced portions 39a and 39b to a position for passage through the slot portions 38b of the keyhole openings 38. When this has taken place, the thumb pressure on the bottom 10 is released, whereupon the spring 69- shifts the pivotshaft 39 to the normal position shown in. Fig. 4 in which the lever 35 is maintained in pivotally. connected-relation to the bracket l 8.

In connection with the bracket [8 and the lever 35 it can well be explained at this point that the bracket provides a hollow mount for the rotary control shaft I4 and that the cams 46a and 46b and the cam follower are located in the recess or chamber of such hollow mount. The lever 35 also forms a hood or cover for the hollow bracket so that these members together constitute a housingfor the cams 46a and 46b and becoming extinguished.

also for the cam follower 45 and the pivot shaft 39-. When the burner Ill embodies this housin featureit hasa relatively smoother and more attractive appearance and the cams, cam follower and pivot shaft will be shielded from damage and from having dust, food particles, grease or other foreign matter collect thereon.

It should also be explained at this point that the bottom wall 36 of the bracket 18 can have an angular portion or lug l2 thereon, as shown in Figs. 3 and '7, which engages in the lower end of the slot '53 of the burner tube I! and thus forms a locating means for the correctpositioning of the burner tube on the plug 24 I In connection with the matter of disassembling the burner for cleaning purposes, it should also be explained that when the lever 35 has been removed from the bracket 18, as explained above, the burner tube H with the shutter member 26 thereon can be easily disengaged from the plug 24. After the burner tube H has been thus disengaged from the plug, the shutter member 20 can be removed from the burner tube by axial sliding thereon in a direction away from the cap 33. 'After the cleaning has been accomplished the shutter member can be reassembled on the burner tubeand the latter again mounted on the plug 24.

The burner I can be provided with any suitable pilot burner and in this instance a pilot burner 74 of a novel construction is employed. The pilot burner 74 comprises an upright burner tube 75 located alongside of the main burner tube Hand having a refractory sleeve or wick 16 in the upper end thereof and which forms a burner tip from which the pilot flame 74a burns. The refractory sleeve 16 can be made of suitable nonmetallic material such as ceramic or asbestos, or can be a suitable fibrous material impregnated with barium sulphate or other suitable chemical.

' main gas burner hasbeen turned on, some of Since this refractory wick is non-metallic in cliar- 'acter it will not transfer heat rapidly and will thus serve to retain the heat of the pilot flame and will become more or less incandescent in characterwhen the pilot flame is burning. This will render the small pilot flame Ma more easily visible and will produce a more efficient burning of the gas with less likelihood of thepilot flame The wick 16 can be mounted on the pilot burner tube 15 by being telescoped partway into the upper end thereof, as shown in Fig; 3, and is preferably disposed so that a portion thereof will project outwardly from the burner tube.

The pilot burner 14 is also provided with a hood "ii which is mounted on the upper end" of the burner tube i5 so as to surround, orv partially surround,the pilot flame Ma. The hood can be mounted on the tube M by providing the-latter with a shoulder against which-the bottom-wall of the hood isclamped by means of the collar '18. The hood 7? has a side wall which is formed by a group of spirally extending blades orlouver elements 19 having their adjacent upright edges in overlapping relation to provide the louver open-. ings 80. The blades '19 permit air to pass through the louver openings 89 to thepilot flame 74a for combustion purposes, and also serve the important function of shielding the pilot flame against direct drafts and air currents which might other- H wise extinguish the same.

Atlthe side next to the main burner tube,

; bustion open'ingBl. The shutter member 94 comthe gas and air mixture escapes through the openings: 82- and is ignited by the flameofthe pilot burner M. Since the openings 82 are located in a row extending up the main burner tube [1 toward the combustion opening 2 I, theflanies produced by the burning of the gas mixturedssuing from these openings will travel up the main burnertube to the combustion-opening and will ignite the main stream of the gas and air mixtureissuingfrom the latter. r

Thepilot burner!!! extends through the forked opening '43, of the lever 35 andis mounted on the base [6 by means of'the hollow body' 83 andthe coupling 84. The pilot burner is mounted on .the couplingfl i by having the lower endoffthe pilot burner tube 'slidably. telescoped 'ovr'mefeylindrical portion 84aof this coupling? The slidable telescoping connection permits the pilot burner to be readily detached from the coupling 84 whenever this is desirable. The body 83 has a passage 83a therein to which gas is su'pplied from the passage 24a of the plug 24 through a lateral passage comprising thedrilled passage portions 85a, 85b and 850. The passageI83d is closed at the lower end of the body 83by 'a-plug which is here shown in the form of a ball 83b;

For controlling and filtering the gas flowing to the pilot burner a filter element 85 is provided in the body 83 so as to extendfacros's the upper end of the passage 83a thereof. This filter element can be made of any suitable material, such as fibrous asbestos, rock wool, glass fibres or the like, which will strain particles of foreigninatter out of the gas stream and will preventithe same from extinguishing or impairing the pilot flame. The size of the pilot flame 14a canbeadjusted by varying the rate of gasflow through the filter element 86 and this can be done by varying the density of the filter element by means of the pressure applied thereto by the lower end of the coupling 84. The density of the filter element 86 can be varied by screwing the coupling .84 inwardly or outwardly of the body. 83 and this can-be efiected by applying a wrench or other suitable tool to the polygonal portion 81 of the coupling.

Figs. 8, 9 and 10 of the drawings: show a. gas burner '80 which is similar to the burner 18' de scribed above but in which the shutter member and the pilot burner are difierently constructed and "arranged.

.The modified burner J 9|} 'is adapted for right and left-hand installation in the same way as the burner H] andembodies similar bracket and lever member's' I8 and :35 and similar pivot and control shafts l4 anass.

In the'modified burner 9% however, theplugid .ofthe gas control valve l9 has a valve seatfii poope'rates with, this valve seat so ,that" inward or downward movement of .the valvegmember tendsto close the orifice and outward of upward movement ofithe, valve member opens the prince.

In this modified burner 99 the shutter member 94 comprises a sleeve assembly which isaxially slidable in the burner tube 95 and is provided at its upper end with a flange orhcap' 96 which cooperates with j the upper end of the prises inner'and outer sleeves 94a. and 94b and intermedlate the ends .thereof., '.Below the plug acetate;

08 the inner sleeve is provided with a central passageSS into which a velocity stream of gas is discharged from the orifice 92 and induces a flow or air into the burner tube 95 through the air inlet opening I thereof. The upper portion of the'shutter member 04 is provided with axial passages IOI extending therealong between the inner and outer sleeves 94a and 94b for conducting the gas and air mixture to the combustion opening 91. The lower ,ends of the passages IOI are connected with the central passage 99 by circumferentially spaced'openings I02 formed in, the wall of the inner sleeve 94a immediately below the plug 98.

The portion of thecentral passage of the inner sleeve 94a which is located above the pmg sa forms a chamber I03 for a pilot burner I04. The plug 98 has oppositely extending outwardly converging' tapered ends on which the valve memwhich filter element corresponds with and serves the same purpose as the above described filter element 80.

' The pilot burner I04 is here shown" as comprising a coupling I04a mounted in the upper end of the plug 08 and a pilot burner tube 'I04b tele's'copingly mounted on the upper'end of such coupling. The pilot burner I04 may also include a non-metallic wick or sleeve I06 mounted in the upper end of the burner tube I04b and corresponding as to purpose and structure with the"above' described nonmetallic wick I5. Air for combustion purposes is admitted to the pilot burner chamber I03 through radial passages I01 of the inner sleeve 94a of the shutter member and which radial passages register with slots I08 formed in the outer sleeve 9413. At a point adjacent its upper end thejmain burner" tube 95 is provided with openings I00 exposing .the slots I08 to the atmosphere. h

" In the modified'burner 00 the orifice 02 and the combustion opening 91 are opened or en'- l'arged by an upward movement of the shutter member 04"instead of a downward'rnovement as is the case in the burner I0. This requires an upward movement of the lever arm. 35a .when the control shaft I4 is rotated in the usual counten-clockwise direction for turning on the burner 00 a'nd is" produced by the action ofa tension spring] I0 having one end connected to the lever arm 35b by means of the eye III' and its'other end anchored on a pin-I I2 which extends thro h the side walls of the bracket I8- The rocking hi the lever 35 by the spring'I I0 to cause opening of thev'alvehmember 93 and of the combustion opening 91 is controlled by apair of cams 113a and 32) mounted on the comic- 1 shaft 14.

Thesecams are of substantially the same shape the cams 46a and 46b of the burner I0 but are in a reversed position with respect thereto so that the rocking of the lever 35 will be in the direction needed for opening and closing actuanon of the valve member 93 and the shutter iiimber 94. Closingmovement of the valve member 03 and the shutter member 94 is produced b'y' the direct action of one of the cams on the follower 45 which rocks thelever 35 on the pivot 12 shaittfl in a direction to swing the lever arm 35a downwardly. At this time the spring II. holds the follower 45 against the face of the cam.

When the burner is being used in a right hand installation the cam II3a cooperates with the follower 45 and when used in a left-hand installation the cam II3b cooperates with the follower. The cams' H311 and H32) carry lugs HM and I I412, respectively, which serve the same purpose as the lugs 51a and 57b of the cams 46a and 46b.

To enable the fingers 42 of the forked end of the lever arm 35a to cooperate with the shutter member 9 4, the outersleeve 94b of the latter-is provided with an annular groove I I5 in which these fingers engage as shown in Fig. l3 and the burner tube 95 is provided at these points with axialslots H6 which afford access to this groove for the fingers 42, as shown in Fig. 10.

The upper end of the inner sleeve 94a of the shutter member 94 is provided with a row of rela- .tively small openings II! which permit some of the gas and airmixture to reach the pilot flame I I8 and be ignited thereby causing the pilot flame to travel around the'cap or flange 9B for igniting the main stream of the gas and air mixture issuing from the combustion opening 91.

Figs. l4, l5 and 16 show a modified burner I20 which is the same as the burner I0 of Figs. 2 to 7 inclusive, except that the shutter sleeve of the burner tube is reversed from the arrangement usedin the burner I0, and consequently, the cap 33 and the valve actuating pin 52 are mounted somewhat differently as hereinafter explained. In other respects the modified burner I20 is substantially the same as'the burner I0 andthe same reference characters have been used on the corresponding parts.

In the modified burner I20 the burner tube I2! is an upright sleeve mountedon the base I6 in the manner explained above for the sleeve ll of the burner I0, and the shutter member I22 is a sleeve slidable in tli'e'burn'er tube and whose upper end is'movable relative to the cap 33 for controlling" thecoinbustion' opening 2|. The cap 33 is mounted in fixed relation on the upper end of the burner tube E2| as' by means'of the circumferentially spaced integral axial extensions I23 to which the cap welded or otherwise secured. The valve actuating pin 52 is' mounted on the shutter member I22 by having its steni extend through an opening 52b thereof and its head 52c recessed into a counterbored portion of such opening. .The forked end of the shutter actuating lever 35 has its opposed finger portions 42 engaged inan annular groove I24 of the shutt er member I22 which is exposed at diametrically opposed points by the axial slots I25 of the burner tube I2I. The slots I25 also provide an air inlet opening at the lowerend of the burner tube.

From the accompanying drawings and the foregoing detailed description it will now be readily understood'that this invention provides an improved constructicn for a gas burner or the gas and air mixing type, in which a shutter member for controlling the delivery of the gas and air mixture is actuated simultaneously with the gas control valve. It will also be seen that m the improved burner construction the gas is 'discharged into the burneftube as a velocity stream which-induces a flow of air into the tube for mixing with the gas and this insures a velocity discharge of the mixture from the combustion opening at all times when the burner has been turned on; Because of this characteristic the improved burner has a very satisfactory turndown ratio and the tendency for the flame to backfire into the burner tube will be minimized or eliminated and the burner will therefore be safe and reliable in operation. It will. also be seen that, since the combustion opening is varied simultaneously with the gas control valve, the air admitted for mixing with the gas will be automatically controlled-as to volume for the most efiicientcombustion of the gas. improved burner is adapted for either right or left-handvinstallation, thus greatly minimizing the number of different burners and parts needed to be kept in stock. Additionally; it will be understood that the cam and lever arrangement provided by this invention affords a direct and accurate means for actuating the shutter member and gas, control valve., As previously explained herein, it will be seen .that the improved construction provides for the quick and easy disassembly of the burner for cleaning purposes.

Although the improved gas burner has been illustrated and described herein to a detailed extent, it will be understood, of course, that the invention is not to be regarded as being limited correspondingly in scope, but includes all changes and modifications coming within the terms of the claims hereof.

Having thus described our invention, we claim:

1. In a gas burner, a support, a mixing tube on said support and having an air inlet opening adjacent one end of the tube, cap means cooperating with the other end of said tube and defining therewith a combustion opening, means for discharging gas in said tube so as to induce a flow of air thereinto through said inlet open- It will now also be understod that the V ing for mixing with the gas and including a movable valve element for controlling the gas discharge, shutter means adapted for opening and closing movements substantially axially of said tube for varying the size of said combustion opening, a rotary shaft on said support and having a cam thereon, a lever having one portion cooperating with said cam and another portion cooperating with said shutter means for transmitting motion to the latter, fulcrum means rockably mounting said lever on said support, means for imparting opening and closing movements to said valve element substantially simultaneously with the respective opening and closing actuation of said shutter means, and cooperating locking elements on said support and cam and being engageable with each other for holding said shaft against rotation when said valve element is in its closed position, said shaft being axially shiftable for disengaging said locking elements so as to permit rotation of said shaft.

2. A gas burner for installation in either of two operative positions comprising, a mixing tube structur provided with an air inlet opening and with a combustion opening for the delivery of a gas and air mixture, a gas control valve having anorifice adapted to discharge a velocity stream of gas into said tube structure'so as to induce av fiow of air into the tube structure through said air inlet opening for mixing with'the gas, shutvalve and substantiallysimultaneous closing-actuation ofsaid shutter means and said control valve including cam follower meanszadapted'to cooperate with one of said cams during rotation of said shaft, said shaft being also axially movable for shifting said one cam out of cooperating relation to said follower means and, simultaneouslyshifting the other of saidcamsinto cooperating relation with said follower means, oneof said cams having a contour adapting said burner for installation in one of said operative positions and the other of said cams having substantially the reverse contour, and adapting said burner for installation in the other of said two positions.

3. A gas burner for installation ineither'of two operative positions comprising, a mixingtube structure adapted to be supplied with gas and air and provided with an opening for delivery of the gas and 'air mixture, shutter means movable relative to said tube structure for, varying the size of saidopening, a rotary shaft, a pair of cams onsaid shaft and spaced apart axially thereof, and means for causing actuation of said shutter means in response, to rotation 'of said shaftincluding cam follower means adapted to cooperate with one of said cams, said shaft being also axially movable for shifting said one cam out of cooperating relation to said follower means and simultaneously shifting the other of said cams into cooperating relation with saidfollower means, one of said cams having a contour adapting said burner for installation in one of said operative'positions and the other of said cams having substantially thereverse contour and adapting saidburner for installation in the other'of said two positions. 7 I

4. A gas burner for installationin either of two operative positions comprising, a mixing tube structure adapted to be supplied with gas and air and provided with an opening for delivery of the gas and air mixture, shutter means movable relative to said tube structure for varying the size of said opening,a double-ended rotaryshaft, a pair of cams on said shaft-and spaced apart axially thereof, means for causing actuation of said shutter meansin response to rotation of said shaft including cam follower means-adapted to cooperate with one of said cams, said shaft being also axially movable for shifting said one cam out of cooperating relation to said follower means and simultaneously shifting 'the other of said cams into'cooperating relation with said follower means, one of said cams having a contour adapting said burner for installation in one ofsaid operative positions and the other of said cams having substantially the reverse contour and adapting said burner for installation in the other of said two positions, and handle means adapted to be connected with one end of said'shaft for im-,

parting rotation thereto while said one cam is in cooperating relation to said follower means and adapted to be connected with the other end I of said shaft for imparting rotation thereto while said other cam is in cooperating relation to-said follower means.

controlling the gas discharge, shutter means :adaptedfor opening and closing movements substantiail-y axially of said tubefor varying the: size of said combustion-opening, a double-ended rotary shaft having a pair of cams thereonand spaced apart axially thereof, follower rmeans adapted-to be-actuated by-one of'saidcams-for imparting opening-and closing movement tosaid shutter means, means for imparting-movements to said valve element substantially simultaneously with the respective'openingandlclosing actuation of said shutter meanspsaid-shaft being axially movable for shifting said one'cam out of cooperating relation to said :follower means and simultaneously shifting the other of said cams into cooperating relation-with said-follower means, one of said cams having a contour adapting said burner for installation in one of said operative positions and the OthL-Of :said

ing-rclation-to said follower means;

6. A gas burner for installation in' either of :two operative positions comprising, a supportgamixing tube on saidsupport and having an air inlet opening adjacent one end-of the tube,a cap cooperating with the other end of said 'tubeand defining therewith a combustion opening, -means for discharging gas in said tube so as to induce a flow of air thereinto through said inlet'opening for mixing with the gas and including a movable valve element for controlling the gas discharge, the shutter means-adapted for openingand closing movements substantially axially of said tube for varying the size of said combustion opening, a double-ended rotary shaft on said support and having a pair of cams thereon and spaced apart axially thereof, follower means adapted to be actuated by one of said cams for imparting opening and closing movementsto'sa'idshutter means, means for imparting opening and-closing movements to said valve element substantially simultaneously with the respective opening andclosing actuation of said shutter means,said shaft being axially --movable for shifting said-one cam outof cooperating relation to said follower means and simultaneously shifting the other of said cams into cooperating -relation with said follower-means, one of'sairl cams having a contour adaptingsaid burner for installation 'in one of saidoperative positions and the other of said cams having substantially the reverse contour and-adapting said burner for installation in the other of said two positions, handle means adapted to 'be connected with one end of said shaft for imparting rotation thereto while said one cam is in cooperating relation to-said follower means and adapted to be connectedwith the other end of said shaft for-impartingrota- 'tion theretowvhile said other ca-m is in cooperating relation-to said follower meansand locking means adapted to releasably hold said shaft in the rotary position corresponding with the closed position of said-valve element.

'7. A gas burnerfor-installation in-eitherof two operative positions comprising abasd-amixing tube structure on said base andprovided with a combustion opening and an air' -'inlet opening, means providing an orifice=for'-discharging :gas lnsaid'tube-for inducing'a now of air thereinto forlmixing with the gas, shutter means'movable relative to said tube structure in opening and closing directions to vary the size of said combustion opening, a valve member movable to control the discharge of gas from said orifice, lever means rockably mounted on said base and cooperating with said shutter means for transmitting movement thereto, a rotary shaft having .apair of cams thereon and one of which coacts with said'lever means to impart movement thereto, means foractuating said valve member iniopening and closing directions substantially simultaneously with the respective opening and closing actuation of said shutter means. said shaft having handle-receiving ends extending in opposite directionsbeyond said cams and said shaft beingaxially movable for shifting said one cam out of cooperating relation to said lever means and simultaneously shifting the other of said cams into cooperating relation with said lever means, one of said cams having a contour adapting said burner for installation in one of said operative positions and the other ofsaid cams having substantially the reverse contour and adapting said burner for installation in the other of said two positions, and handle means adapted to be connected with one end ofisaid shaft for imparting rotation thereto whilesaid one cam is in cooperating relation to said lever ,means and adapted to be connected with the otnerend ;of said shaft forlimparting rotation ther o awh 1 3 other cam is co peratin vrelationto said lever-means. v a

8. A;ga s burner comprising, asupport, a mix- ;ing tube structure on said support and having an ;air inlet opening ;and a combustion opening,

means for discharging gas in said tube structure so as to induce a fiow of air thereinto through said inlet opening andincluding a movable valve element forcontrolling the gas-discharge, a shut ter member movable relative to said tube structure substantially axially thereof and in opening and closing directions for varying the size of said combustion opening, a bracket on said support and havingarecess therein, a rotary shaft having a cam thereon and located in the recess of said bracket, a leverpivoted on said bracket and being of a shape to form a cover for the bracket recess, said lever having one portion coacting with said cam and-another portion coacting with said shutter member for transmitting motionfto the latter, and means for utilizing movement of said shutter member for causing opening and closing actuation of said valve element substantially simultaneously with the respectiveopening and closing actuation of said shutter member.

9. A gas burner comprising, asupport, a mixingtubestructure on said support and having an air inlet opening and. a combustion opening, means for discharging gas in'said tube structure so as to induce a flow ofnair thereinto through said'bracket, alever pivoted on said bracket and having a'body of a shape to-form acover for the bracket'recess, said'lever having a portion coacting-withsaid shutter member for imparting shut- -ter member actuating movement thereto and a follower portion coactingwith said cam and adjustable relative to said body, and means for utilizing movement of said "shutter member for causing opening andclosing actuation of said valve element substantially simultaneously with the respective opening and closing actuation of said shutter member? 3 10. A gas burn'ercomprising, a support, a mixing tube structure on said support and having an air inlet opening and a combustion opening, means for discharging gas in said tube structure so as to induce a flow-of air thereinto through said inlet opening and including a movable valve element 'forc'ontrollingthe gas discharge, a shutter member movable'relative to said tube structure substantially axially thereof and in opening and closing directions for-varying the size of said combustion opening, a hollow bracket on said support and having spaced side Walls, a rotary shaft extending through said side Walls and having a cam thereon located in the space between the sidewalls, a sheet metal bell crank lever having a body of a shape to form a cover for said hollow bracket, a pivot shaft mounting said lever on said bracket and having'quick-releasable engagement with said side walls for detachably connecting said lever with the bracket, said lever having one arm 'coacting with said shutter member for imparting shutter member actuating movement thereto and another arm provided with a follower portion coacting with said cam, and means for utilizing movement of said shutter member for causing opening and closing actuation of said valve element substantially simultaneously with the respective opening and closing actuation of said shutter member.

11. A gas burner for installation in either of two operative positions comprising, a support, a mixing tube structure on said support and having an airinlet opening and a combustion opening, means for discharging gas in said tube structure so as to induce a flow of air thereinto through said inlet opening and including a movable, valve element for controlling the gas discharge, a shutter member ,movable relative to .4

said tube structure'substantially axially thereof and in opening and closing directions for varying the size of said combustion opening, a hollow bracket on said support. and having spaced side walls, a'rotary shaft extending through said side walls and having a pair of cams thereon and located in the space between said side walls, a lever pivoted on said bracket and having arm and follower portions coacting respectively with said shutter member and one of said cams, said shaft having handle-receiving ends extending beyond said side walls and said shaft being axially movable for shifting said one cam out of cooperating relation to the follower portion of said lever and simultaneously shifting the other of said cams into cooperating relation with the follower portion of said lever, one of said cams having a contour adapting said burner for installation in one of said operative positions and the other of said cams having substantially the reverse contour and adapting said burner for installation in the other of said two positions, means for utilizing movement of said shutter member for causing actuation of said valve element substantially simultaneously with the actuation of said shutter member, handle means adapted to be connected with one end of said shaft for impart ng rotation thereto while said one cam is in cooperating relation to said follower portion and adapted to be connected with the other end of said shaft for imparting rotation thereto'whilesaid other cam is in cooperating relation to'said follower portion, and locking elements on one of said cams and an adjacent side wall 'of the: bracketand adapted for locking coaction for holding said shaft against rotation when said valve' element is closed U f I1,

12. A gas burner comprising, 'a support, a'mixing tube structure on said support and having an air inlet opening and 'a' combustion opening, means for discharginggas-in said tube structure in opening and closing directions so' as -to induce a flow of air thereinto through said inlet opening and including a movable valve element for controlling the'g'as discharge; a shutter'mernber movable coa'xially of said'tube for varying the size of said combustionopening'; a bracket'on said support adjacent said tube structure, a rotary shaft supported by said bracket and having a cam thereon, a lever pivoted on said bracket and having a follower portion coacting with said cam and an arm portion extending between the bracket and tube and coacting with said shutter member for imparting the coaxial movement thereto, means for causing actuation of said valve member in opening and closing directions substantially simultaneously with the opening "and closing movements of said shutter member, said bracket having opening means therein," and a pilot burner devicelocated between said tube structure and said" rotary shaft and extending through the opening means ofsaid bracket.

13. In a gas burner, asupport, a burner tube having inner and outerendsgsaid burner tube having its inner endconnected with said support and also having an' air inlet opening adjacent said inner end, a shutter member having cap means on its outerend disposed in cooperating relation to the'outer end of said tube and defin ing with the latter a mixture delivery opening, said shutter member'being-axially movable in said tubeto cause opening and closing movements of said cap means for varying the size of said delivery opening, said shutter'mer nberhaving an axially extending passage therein for cond'ucting a gas and air mixture to' said delivery opening,

means on said support providing an orifice for discharging gas into said tubeso as to induce a 'flow of airthrough said inlet opening for mixing with the gas, a valve element insaid tube and connected with said shutter'memberand be'-' ing movable with the latter for controlling the discharge of gas from said orifice, means operable to impart movement to said shutter member for varying said delivery opening and actuating said valve element, and a pilot burner mounted on said shutter member, said valve element having a passage therethrough for supplying gas to said pilot burner.

14. In a gas burner, a support, a burner tube having inner and outer ends, said burner tube having its inner end connected with said support and also having an air inlet opening adjacent said inner end, a shutter member having cap means on its outer end disposed in cooperatingrelation to the outer end of said tube and defining with the latter a mixture delivery opening, said shutter member being axially movable in said tube to cause opening and closing move ments of said cap means for varying the size of said delivery opening, said shutter member comprising coaxial inner and outer sleeves having a conduit space therebetween for conducting a gas and air mixture to said delivery opening and a partition in the central passage of said inner sleeve at an intermediate point thereof, the wall of said inner sleeve having an opening therein connecting said conduit space with the portion the central passage oi the inner sleeve extending below said partition, means on said support providing an'orifice for discharging gas into said inner sleeve so as to induce a flow of air through said inlet opening for mixing with the gas, a valve element connected with said partition and movable with said shutter member for controlling the discharge of gas from said orifice, means operable to impart movement to said shutter member for varying said delivery opening and actuating said valve element. and a pilot burner in said inner sleeve and mounted on said partition, said valve element and partition having a passage therethroug-h for supplying gas to said pilot burner.

15. A gas burner as defined in claim in which the second mentioned arm of said bell crank lever is resiliently flexible to permit adjustment of said follower portion, and in which an adjusting means carried by the lever cooperates with the resiliently flexible arm.

16. In a gas burner, a support having therein a bore and an orifice adapted to deliver a velocity stream of gas, a mixing tube having an inner end connected with said support and an outer end and being disposed in substantially coaxial relation to said orifice to receive said velocity stream therefrom, said tube having an air inlet opening adjacent said inner end for admission of air for mixing with said gas. cap means cooperating with the outer end of said tube and defining therewith a combustion opening for the gas and air mixture. a tubular shutter member coaxially slidable relative to said tube in opening and closing directions ior'varying the size of said combustion opening, a valve member movable in said bore in opening and closing directions for controlling said orifice and having a stem projecting through said orifice and extending axially in said mixing tube, a spring in said bore urging said valve member toward closed position, a control shaft rotatably mounted on said support, cam and lever means operable in response to rotation of said shait for imparting the sliding movement to said shutter member, and means carried by said shutter member and engageable with said stem ior imparting opening movement to said valve member.

17. A gas burner as defined in claim 16 in which said control shaft is offset from said mixing tube and is disposed with its axis extending in transverse relationto the axis or said mixing tube;

1 8. In a gas burner, a support having therein an orifice adapted to deliver a velocity stream of gas, an upright mixing, tube having its lower end connected with said support and being disposed in substantially coaxial relation to said orifice to receive said velocity stream therefrom, said mixing tube having an air inlet opening adjacent its lower end for admission of air for mixing with said gas, a tubular shutter member axially slidable in said tube and having means cooperating with the upper end of said tube for defining therewith a combustion opening, a valve member extending coaxially in said shutter member and connected for movement therewith and having its lower end extending into and controlling said orifice, a control shait rotatably mounted on said support, cam and lever means operable in response to rotation or said shaft in one direction for causing closing actuation of said shutter member and valve member, and spring means adapted to supply an actuating force ior causing opening movement of said shutter member and valve member during rotation of said shaft in the opposite direction.

PAUL F. SWENSON. MILTON F. PRAVDA.

REFERENCES CITED The following reier-ences are of record in the file of this patent: I

UNI'IED.'STA'IES PATENTS Number .Name Date 366,261 Ruppel July 12, 1887 926,300 Stubbers June 29, 1909 1,009,678 Mavrogordato Nov. 21, 1911 FOREIGN PATENTS Number Country Date 131,498 Germany .June 9, 1902 211,271 Germany June 25, 1909 19,493 France Nov. 10, 1914 162,641 Great Britain Feb. 4, 1921 258,632 Great Britain Sept. 17, 1926 27,196 Netherlands July 15, 1932 

